My understanding of GDPR is that it contains a number of exceptions for financial institutions and services. If are European you can request for your data to be deleted, but if the data is linked to financial transactions, then the company in question is within their rights to hold on to a subset of the data for a number of years for anti-money laundering purposes.

Also, your post history talks about trading in dollars, while your website says it is headquartered in Delhi. Neither the US nor India are subject to GDPR, given that it is a European regulation.

Do you have any proof that CoinPayments are selling personal data?